Substance profile
Isoprene
Isoprene is a colorless volatile liquid with a petroleum-lke odor.
01 · Identification
What Isoprene is
Isoprene is a colorless volatile liquid with a petroleum-lke odor. Its molecular formula is C5H8 and its molecular weight is 68.12 g/mol. It boils at 34.1 °C, melts at -146 °C.
Under the GHS it carries the signal word Danger. It is classed as carcinogens.
Other names for Isoprene
- isoprene (stabilised)
- 2-methyl-1,3-butadiene
02 · GHS classification
Hazards and label elements
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
| Code | Hazard statement |
|---|---|
| H224 | Extremely flammable liquid and vapour. |
| H350 | May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H341 | Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H412 | Harmful to aquatic life with long lasting effects. |
Precautionary statements: P201, P210, P233, P241, P242, P273, P280, P308, P313, P403, P501
03 · Physical and chemical properties
Isoprene properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 34.07 °C (93.3 °F) | HSDB | |
| 33.89 °C (93 °F) | at 760 mmHg | CAMEO | |
| 34 °C (93.2 °F) | ICSC | ||
| Melting point | -145.95 °C (-230.7 °F) | HSDB | |
| 30 °C (86 °F) | HSDB | ||
| -120 °C (-184 °F) | CAMEO | ||
| Density | 0.7 g/cm³ | ICSC | |
| 0.679 g/cm³ | at 20 °C | HSDB | |
| 0.681 g/cm³ | at 20 °C | CAMEO | |
| Solubility | Practically insoluble in water | HSDB | |
| Miscible with ethanol, ethyl ether, acetone, benzene | HSDB | ||
| In water, 642 mg/L at 25 °C | at 25 °C | HSDB | |
| Vapor pressure | 399.033 mmHg | at 20 °C | ICSC |
| 550 mmHg | at 25 °C | HSDB | |
| 400 mmHg | at 15.4 °C | HSDB | |
| Flash point | -53.89 °C (-65 °F) | HSDB | |
| Autoignition temperature | 395 °C (743 °F) | HSDB | |
| 220 °C (428 °F) | ICSC | ||
| Lower explosive limit (LEL) | 1.5 % by volume | HSDB | |
| 1 % by volume | HSDB | ||
| 2 % by volume | CAMEO | ||
| Upper explosive limit (UEL) | 8.9 % by volume | HSDB | |
| 9.7 % by volume | HSDB | ||
| Vapor density | 2.35 (air = 1) | HSDB | |
| 2.4 (air = 1) | ICSC | ||
| Critical temperature and pressure | 211.11 °C (412 °F) | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling Isoprene
Storage conditions
Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Recommended storage temperature 2 - 8 °C.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
Mixing isoprene and chlorosulfonic acid in a closed container caused the temperature and pressure to increase.
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
ISOPRENE may react vigorously with strong oxidizing agents. May react exothemically with reducing agents to release hydrogen gas. May undergo exothermic addition polymerization in the presence of various catalysts (such as acids) or initiators. Undergoes autoxidation upon exposure to the air to form explosive peroxides. Mixing isoprene in equal molar portions with any of the following substances in a closed container caused the temperature and pressure to increase: chlorosulfonic acid, nitric acid (70%), oleum, sulfuric acid (90%) [NFPA 1991].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Isoprene in the storage compatibility matrix →